The principle of a thermocouple, due to Seebeck's discovery is a circuit formed by using two different kind of metal conductors which are joined at the ends. A temperature differential at each end will produce a voltage.

The resultant electromotive forces will be proportional to the temperature difference between junctions.

A thermocouple is a temperature sensor.

Thermocouple is the most suitable method for measuring temperature, sometimes the only method. The thermocouples are used between others for nuclear reactors, nuclear submarines, jet aircraft, industrial kilns and other industrial heat treatment (measure and control of temperature).

The thermocouples can be created with numerous combinations of alloys.

Our thermocouples can be used to measure temperature - 200 ° C to 1260 ° C.

Thermocouple alloys most commonly used are the types E, J, K, N and T.

Type E
The thermocouple is interesting to measure temperatures. It also has the advantage of not having a magnetic response. It is used in applications requiring high values of EMF and resistance to oxidation in a higher range of working temperatures ranging from 150 ° C to 870 ° C. It is sometimes used in thermal generators (in thermopiles). Arranged in series, a thermopile can measure very small temperature differences very clearly.

Type J
Works well in a vacuum and in a temperature range of 0 to 750 ° C, but not recommended for low temperatures, because of problems of oxidation of iron, and in the sulphurous atmosphere above 500 ° C because of the risk of oxidation and embrittlement.

Type K
It allows a measure in a wide temperature range: -270 ° C to 1260 ° C in the treatment of industrial furnaces, manufacturing operations and some of the most requested applications such as nuclear reactors or jet aircraft. It is particularly recommended in oxidating or inert atmospheres.

Type N
Its good stability and good resistance to high temperatures (-270 to 1300 ° C) and oxidation make this thermocouple interesting for measurement at high temperatures and in vacuum, as in the aerospace, nuclear industries and semi - drivers.

Type T
The thermocouple is particularly suitable for use at low temperatures (-200 to 350 ° C) as for cryogenic applications.

RESCAL has developed specific casts for application "thermopile". The particularity of these alloys is to have the ability to develop the highest EMF from all referenced thermocouples never developed until today by the Seebeck's effect. These alloys are used when seeking higher electromotive force, which, in turn, will facilitate the piloting of electronic measuring devices.
 
These systems are particularly requested for the leading of equipment where safety is a priority (for sensors flames of gas, safety valves ...).